fix(build): pin npm version in appveyor to v3, compat with node 4 (#2983)
fix(build): pin npm version in appveyor to v3, compat with node 4 (#2983)


karma-runner/karma,johnjbarton/karma,maksimr/karma,karma-runner/karma,david-garcia-nete/karma,karma-runner/karma,david-garcia-nete/karma,karma-runner/karma,johnjbarton/karma,david-garcia-nete/karma,johnjbarton/karma,johnjbarton/karma,maksimr/karma,maksimr/karma